Xperia XZ Premium not charging and not starting

Xperia XZ Premium not charging and not starting

I have connected the phone to the USB lead and to a wall socket. A tiny red light comes on in the top left corner of the phone and a charging logo appears on the screen of the phone. This logo has one red bar on it. The logo then disappears, reappears a few seconds later and then disappears again. Then, about every 90 seconds the same logo, with red bar, reappears twice, and then disappears. I have left the phone on charge for about 12 hours and the phone will still not start up when I press the power button and hold it for 10 seconds, it does not vibrate.